Revenues from eSports and streaming game content will reach $3.5 billion by the year 2021, according to a new report from Juniper Research. That's up from approximately $1.8 billion in 2016. This near-doubling of revenue growth over five years represents the increasing popularity of both eSports and video game personalities on platforms like Twitch.

"The past five years have seen viewership of eSports competition rocket," says the report. For example, the final stages of the three biggest eSports tournaments of 2016 saw over 90 million unique viewers. Those are figures that rival those of some traditional sports competitions. The biggest so far, the report notes, is the 2016 League of Legends World Championship, which saw 43 million viewers.

The report states one of the drivers for earnings increases is bigger prize pools in eSports tournaments, which are traditionally sponsored but are also built up by crowdfunding. Juniper notes that Valve, in particular, has benefited from crowdfunding.

"[Valve] used crowdfunding to bolster the $1.6 million base prize pool for its annual 'The International' Dota 2 tournament," the report states. "$19.2 million was contributed to the 2016 edition in 89 days through the purchase of in-game items and passes for Dota TV."

In terms of streaming video games, the report features Twitch as the dominant player over rival YouTube. Juniper expects that Twitch will capture over 83% of total eSports viewers in 2017 compared to YouTube. The report highlights the fact that one reason for Twitch's dominance is that videos on the platform, "are frequently more polished and appear better designed to maximize engagement, as well as provide a revenue stream for their owners."